Setsuna Mudo, a 16-year-old high school student, is just trying to make it through the day without getting in trouble with his bullies. He's in love with his younger sister, Sara, who only sees him once a month, which doesn't help matters. But his existence isn't only about keeping his head down. Setsuna is confronted by a slew of mysterious entities, angels, and demons, all claiming to know his actual fate. The angels think he is the reincarnation of their commander Alexiel, while the demons claim he led them into a battle with God himself.